Moong-chi, a feisty, playful dog abandoned by his owners joins a pack of strays and comes to terms with his unwanted and abrupt freedom. With his new friends in tow, Moong-chi heads north and finds the perfect place of safety and peace -- the demilitarized zone between North and South Korea.
A rat is killed for food; there's no blood, but the animal is obviously dead. Later a deer is also killed for food. Blood isn't shown on the animal, but is shown on the muzzles of the dogs eating it.
In the sense of humans forcing dogs to fight, there's a flashback scene where this is indicated to have happened in the past. There are also scenes of dog choosing to fight each other. These aren't overly graphic and involve dogs getting knocked out. There's no visible blood.